This invention relates to an apparatus for drawing-up and winding-up booms, preferably so called self-expanding booms, each boom being provided with an upper floating body portion and a lower skirt portion, which apparatus comprises a plate arranged on a platform, which plate is rotatable by means of a motor unit, and which is provided with a winding-up means positioned essentially vertically and essentially at the middle of the plate, and a means for feeding-in the boom, the platform and the motor unit being designed in that way that the motor unit can be plugged into and out of the platform, and the plate being designed in that way that it can be driven by means of a gear pinion which is arranged in the motor unit and goes into engagement with the plate when the motor unit is plugged into the platform.
Such an apparatus is previously known by the allowed and printed Swedish patent application 465.277. This apparatus functions very well in normal cases when winding up booms. In this known apparatus as well as in other apparatuses in the market, however, there can be problems if the the boom, being drawn up, is made extremely dirty with oil. This problem consists of the fact that the boom slides down on the "roll" during the rolling-up phase, whereby the "roll" becomes ungainly and unnecessarily space-requiring.